1. Field of the Invention
The invention relates to a watertight connector that uses a gelatinous material.
2. Description of the Related Art
A watertight connector that uses a gelatinous material is known, for example, from Japanese Unexamined Patent Publication No. 2000-348816. This watertight connector has a male housing with a receptacle and a female housing. A gelatinous material is provided in a gelatinous material accommodating space at the back surface of the receptacle of the male housing. The gelatinous material is squeezed between the gelatinous material accommodating space and the leading end of the female housing when the housings are connected. Thus, the gelatinous material flows to seal clearances between the housings for achieving a watertight fit. However, the squeezing of the gelatinous material increases the connection resistance, and thus leads to a poor operability. The present invention was developed in view of the above problem and an object thereof is to provide a watertight connector having an improved operability.
The invention is directed to a watertight connector that has a first housing and a second housing with a receptacle into which the first housing can be fit. A gelatinous material accommodating space is provided at a back surface of the receptacle, and a gelatinous material is accommodated in the gelatinous material accommodating space. The gelatinous material is squeezed as the two housings are connected with each other to provide a watertight fit. An escaping space is formed between an outer surface of the first housing and an inner surface of the receptacle and is continuous with the gelatinous material accommodating space. Thus, the gelatinous material is squeezed during the connection of the two housings and can at least enter the escaping space.
The prior art watertight connector has a small clearance continuous with the gelatinous material accommodating space. However, the clearance is only sufficiently large to permit the connection of the two housings. Thus, the gelatinous material is squeezed as the housings are connected and is pressed in this small clearance. Resistance from the flow of the gelatinous material becomes excessively large, which further leads to a large connection resistance of the two housings. In contrast, the watertight connector of the invention permits the gelatinous material to escape into the escaping space. As a result, resistance caused by the gelatinous material is reduced and operability is improved. Thus, the invention provides a watertight connector with a smaller connection resistance despite a construction in which the housings squeeze the gelatinous material during connection.
The escaping space is formed by a clearance between the inner surface of the receptacle and the outer surface of the first housing over substantially the entire peripheral surfaces. Thus, the gelatinous material enters the escaping space over substantially the entire peripheral surfaces during connection of the housings, thereby providing satisfactory sealing over substantially the entire periphery of the front surface of the first housing.
The escaping space may be formed by a slanted surface on the inner peripheral surface of the receptacle that is widened toward an opening side of the receptacle. Thus, the gelatinous material can be accommodated easily into the gelatinous material accommodating space without getting caught.
The gelatinous material accommodating space may have an extension along a longitudinal direction of the watertight connector that is smaller than the thickness of the gelatinous material in an uncompressed state.
The gelatinous material accommodating space may have a volume smaller than the volume of the gelatinous material in an uncompressed state so that the gelatinous material can project out from the gelatinous material accommodating space. Accordingly, a squeezing effect can be improved, since the gelatinous material already projects from the gelatinous material accommodating space in an uncompressed state.
The gelatinous material accommodating space may be slightly larger than a leading end of the first housing. Accordingly, the first housing can be inserted into the gelatinous material accommodating space to improve the squeezing and the waterproofing.
The second connector housing preferably has at least one terminal fitting that can pierce through the gelatinous material accommodating space before the first housing is mated.
The first housing may comprise a base with an outer surface that is cross-sectionally slightly smaller than an inner surface of the receptacle.
Accordingly, the outer shape of the base end is formed to minimize the clearance between the base end and the inner peripheral surface. Thus, the connectors can be guided smoothly during connection and are shaken to a smaller degree.
These and other objects, features and advantages of the present invention will become more apparent upon reading of the following detailed description of preferred embodiments and accompanying drawings. It should be understood that even though embodiments are separately described, single features thereof may be combined to additional embodiments.